Nasal air filter



FIG. 1 is a front elevation view of a nasal air filter showing our new design;

FIG. 2 is a side elevation view;

FIG. 3 is a top plan view;

FIG. 4 is a bottom plan view; and,

FIG. 5 is an isometric view of a nasal air filter showing our new design.

The dotted lines showing an exemplary users nose is for illustration only and forms no part of the claimed design. 

The ornamental design for a nasal air filter, as shown and described. 